Score the fish on both sides with a deep "tick- tac-toe" cut.
Season with salt and pepper and coat with flour.
Saute in oil until very crispy; dry it out on purpose so that the juice you put on it soaks into the meat. Set aside.
Saute the onions and peppers until limp-add all other items, bring to a boil.
Place the fish in a baking dish and cover with the onion mixture-cover and bake until tender-15-20 minutes.
Notes
Traditionally this dish is made ahead of time and served cold or at room temp. I like it hot, warm or cold. It is a kind of casual picnic item served with a hearty bread.